Both chemically driven and mechanically operated spray dispensers have been in use for many years and are still popular due to their convenience. However, aerosol dispensers that use chemical propellants have come under increasing scrutiny and restrictions are being imposed upon them due to their adverse impact upon the environment as well as the hazards associated with handling them and related insurance issues. Also, conventional non-chemical mechanical spray dispensers are typically unfavorably compared with chemically driven aerosols because they are bulky and commonly require multiple steps in their operation, making them difficult to operate, especially by persons suffering from diseases or disorders such as arthritis. They also require a large number of parts and a large amount of material to produce them, which due to the increasing cost of energy makes them prohibitively expensive to manufacture. This, in turn, makes them too costly for use at the lower price range of consumer products. Moreover, there is a general reluctance to change from the pressurized propellant-driven aerosol systems including bag in a can or piston in a can devices.
Some mechanically operated aerosol devices incorporate storage chambers that require a step in which a metered amount of product must first be obtained and then transferred into a power chamber that provides the pressure for dispensing the product over a certain duration. These types of devices are energy inefficient and degrade over time and or usage, as well as being too costly due to their exotic material structure and dynamic nature for use with a range of desirable products that currently use finger pumps or chemical aerosol valves. Bag in a can devices are complex systems that do not have all the attributes of chemical aerosol delivery.
By way of example, U.S. Pat. Nos. 4,387,833 and 4,423,829 exhibit some of the above shortcomings.
U.S. Pat. No. 4,147,280 to Spatz requires dual separate helixes and a cap for unusual manipulation to deliver product as a spray. U.S. Pat. Nos. 4,167,041, 4,174,052, 4,174,055, and 4,222,500 to Capra et. al., U.S. Pat. No. 4,872,595 to Hammet et. al., U.S. Pat. No. 5,183,185 to Hutcheson et. al. and U.S. Pat. No. 6,708,852 to Blake all require a storage chamber. In addition, Blake requires multiple actions to set up.
Other patents for reference are U.S. Pat. No. 4,423,829 and U.S. Pat. No. 4,387,833 that may be of interest. All have drawbacks in expense for commercial acceptance and feasibility if mass produced at high levels in existing market applications.
Despite the efforts of such devices as shown in the forgoing patents, there remains a need for a more convenient to use, less expensive, and compact mechanically energized duration spray mechanism that performs to dispense product comparably to the chemically energized dispensers in common use. Specifically, it would be desirable to have a one turn actuated duration spray pump delivery system that is free of the disadvantages seen in conventional chemical and mechanically energized aerosol dispensers.